The President and CEO of U.S. gene sequencing device maker Illumina Inc said he had no comment to make about a $5.7 billion cash takeover offer for the company by Swiss drugmaker Roche Holding AG's. "We have no comment at this time," Jay Flatley said in an email to Reuters. Roche, the world's largest maker of cancer drugs, said it would offer to acquire all shares of Illumina for $44.50 per share in cash, an 18 percent premium to Illumina's Tuesday close price of $37.68 on the Nasdaq.